The present invention is related to a rail-type grounding terminal structure composed of a metal grounding member and an insulating housing. The grounding member has such a configuration that the amount of waste material produced in manufacturing of the grounding member is reduced. In addition, the grounding member has larger contact face to increase current value. Also, a gap is defined between the grounding member and the insulating housing to provide an operation space.
A conventional metal grounding terminal is enclosed in an insulating housing (generally made of plastic material). A row of such grounding terminals is latched on a grounding rail (or conductive rail) to establish a common grounding device for electric appliances or mechanical equipments. The grounding device serves to conduct and remove the voltage or static remaining in the machines. U.S. Pat. No. 5,362,259 discloses a typical ground conductor terminal.
The ground conductor terminal includes an insulating housing in which a leaf spring mount or a conductive board is installed. The leaf spring mount or conductive board has multiple wire connectors for connecting with the grounding wires coming from the machines or equipments. A metal grounding member is connected on the leaf spring mount or conductive board by means of welding or riveting. The metal grounding member has two ends latched on the grounding rail (or conductive rail).
In the case that the ground conductor terminal needs to be replaced due to short-circuit or burnout, an operator can use a tool (such as a screwdriver) to hook and pull a hook-shaped foot section formed on lower side of the insulating housing. At this time, the foot section urges one end of the grounding member to bias outward so as to unlatch the grounding member from the rail. However, it often takes place that when the operator uses the tool to pull the foot section, simply the foot section is pulled, while the end of the metal grounding member is not pulled and unlatched from the rail at the same time. In this case, the ground conductor terminal is not separated from the rail. This is because the insulating housing is generally made of plastic material and the grounding member is fixedly welded or riveted on the leaf spring mount. Therefore, when the insulating housing is biased and deformed, the metal grounding member can be hardly truly pulled and unlatched from the rail. Under such circumstance, it is more troublesome and difficult for a serviceman to detach the ground conductor terminal from the rail.
Another issue of such grounding terminals is that when they are applied to high-load industrial power, they have to be able to bear high load. Therefore, for increasing the load or current value of the grounding terminals, it is available to increase the contact area of the grounding terminals. However, the conventional grounding terminals are made by means of forging or linear cutting machine and hard to have large contact face. It is because the cost for using the forging or linear cutting machine to manufacture grounding terminals with large contact face. In practice, according to actual load requirements, it is tried by some manufacturers to arrange grounding terminals side by side in the insulating housing to enlarge contact face or increase current value of the grounding terminals. However, it is still quite troublesome to make such arrangement. Moreover, the side-by-side arranged grounding terminals have many contact points or contact faces, which will lead to increased resistance value. This will directly affect the quality of passing of the current or even cause over-rising of temperature.
In this field, it is required to tightly latch the metal grounding member with the rail so as to reduce resistance. In other words, it is a dilemma to on one hand make the metal grounding member tightly latched with the rail and on the other hand allow a serviceman to easily detach the ground conductor terminal from the rail. In addition, the grounding terminal is required to have larger contact face or current value. Also, it is specifically required to minimize the amount of waste material produced in the manufacturing process. The prior art fails to teach or disclose any measure for solving the above problems.